The present invention relates to a novel amphiphilic diacetylene compound having both of a hydrophilic group and a hydrophobic group, and also relates to a film prepared therefrom.
Heretofore, there are known symmetric diacetylene compounds of the formula: EQU R--C.tbd.C--C.tbd.C--R
wherein R is carboxyl group or an organic group having an ester group, a sulfonate group, urethane bond or hydroxyl group, as described in U.S. Pat. Nos. 3,501,308 and 4,384,980. In U.S. Pat. No. 3,501,297, there are disclosed symmetric diacetylene compounds having carboxyl groups or groups containing an ester group at both ends and having at least two methylene groups which bond the end groups to the diacetylene.
On the other hand, as asymmetic diacetylene compounds, there are disclosed in U.S. Pat. No. 3,501,297 compounds having carboxyl group and benzene ring. In the asymmetric diacetylene compounds, however, the diacetylene bond and the benzene ring or the carboxyl group are not directly conjugated and an ester bond is between the diacetylene and the benzene ring.
A stable monomolecular film cannot be prepared even if a solution of the symmetric diacetylene compound (disclosed in U.S. Pat. No. 4,384,980) or the diacetylene compound having carboxyl group (disclosed in U.S. Pat. No. 3,501,297) in a proper solvent such as chloroform, n-hexane or benzene is spreaded on water surface, because the compound does not have a hydrophobic molecular structure of an appropriate length. Further, the compounds cannot provide a built-up film (L-B film) by means of Langmuir-Blodgett method.
In addition, there are facts that the linear diacetylene compounds redily form a single crystal and that the compounds can be polymerized in solid state with ultraviolet rays, .gamma.-rays, heat and the like. Also, multilayered thin films such as L-B films can be photopolymerized [G. Lieser, B. Tieke and G. Wegner, Thin Solid Films, 68, 77(1980)].
Heretofore, there has not been known as asymmetric diacetylene compound having both of carboxyl group and benzene ring which are conjugated with the diacetylene group. Accordingly, there has not been known, of course, a monomolecular film or a built-up film prepared from such a compound.
An object of the present invention is to provide an amphiphilic diacetylene compound which has a hydrophilic molecular structure such as carboxyl group or hydroxyl group, benzene ring and an hydrophobic molecular structure such as a chain having an appropriate amount of methylene groups, and has properties of conjugated triple bond.
Another objects of the present invention is to provide a monomolecular film and a built-up film prepared by using the amphiphilic diacetylene compound.